1. Field of the Invention
The present invention generally relates to a wireless communication system. More particularly, the present invention relates to a method and system for transmitting and receiving a signal in multiple frequency bands.
2. Description of the Related Art
The development of wireless communication systems is a driving force behind increasing demands for various types of services and a large amount of service data. To satisfy the demands, broadband wireless communication systems have emerged. Limited frequency resources of the wireless communication systems leads to limited frequency bands available to the broadband wireless communication systems. Nevertheless, the demand for frequency bands is increasing to provide broadband services.
FIG. 1 illustrates a single-frequency band support structure and a two-frequency band support structure in a conventional wireless communication system.
In a wireless communication system, particularly a broadband wireless communication system based on Institute of Electrical and Electronics Engineers (IEEE) 802.16, a Base Station (BS) manages one or more Frequency Assignments (FAs) and provides services to Mobile Stations (MSs) in the FA or FAs.
Referring to FIG. 1, an MS 100 can move from a first FA 120 (FA1) to a second FA 140 (FA2). If the MS 100 operates in only one FA or the two FAs 120 and 140 are operated by different BSs, the MS 100 receives a service in FA2 by inter-FA handover.
As compared to the MS 100, if an MS 150 is capable of operating in two or more FAs or the same BS operates two FAs 160 and 180 (FA1 and FA2), the MS 150 can receive a service in the FAs 160 and 180. Transmission and reception of signals between the MS and the BS in multiple frequency bands facilitates high-speed, large-data data transmission and reception. However, no procedures have been agreed between the MS and the MS so far for using multiple frequency bands between them. Moreover, there is no technique for specifying an FA in which the MS will communicate after an inter-FA handover or network entry and network re-entry.